Where does “ércbányák” come from?

ércbányák (Hungarian) comes from Hungarian ércbánya, from Hungarian érc, from German Erz, from Middle High German arze, from Old High German aruzzi, from Proto-Germanic aruts, from Proto-Germanic arud-, from Sumerian ? — copper.

Ancestry of “ércbányák”, step by step

StepLanguageWordMeaning
1Hungarianércbányaore mine
2Hungarianércore
3GermanErzore
4Middle High Germanarze—
5Old High Germanaruzzi—
6Proto-Germanicarutsore
7Proto-Germanicarud-—
8Sumerian?copper
Every word from Sumerian ? →Every word from Proto-Germanic arud- →Every word from Proto-Germanic aruts →